Depreciation and amortization of property and equipment is calculated on the straight-line method based on the shorter of the estimated useful life or the term of the lease for tenant improvements and three to ten years for all other property and equipment. Property and equipment consist of the following (in thousands):


	March 31, 2026			December 31, 2025
Manufacturing and testing equipment	$	4,933		$	5,630
Leasehold improvements		869			848
Computers and software		561			561
Furniture, fixtures and equipment		397			400
Vehicles		55			55
Software development – internal use		74			74
Construction in process		50			16
Property and equipment, gross		6,939			7,584
Less accumulated depreciation		(5,348	)		(5,888	)
Property and equipment, net	$	1,591		$	1,696

Depreciation expense was $0.1 million for each of the three months ended March 31, 2026 and 2025. Accumulated depreciation for the quarter included $0.6 million that was related to disposal of manufacturing and testing equipment and furniture, fixtures and equipment.